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1.
Hum Mol Genet ; 29(9): 1520-1536, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32337552

RESUMO

Here we define a ~200 Kb genomic duplication in 2p14 as the genetic signature that segregates with postlingual progressive sensorineural autosomal dominant hearing loss (HL) in 20 affected individuals from the DFNA58 family, first reported in 2009. The duplication includes two entire genes, PLEK and CNRIP1, and the first exon of PPP3R1 (protein coding), in addition to four uncharacterized long non-coding (lnc) RNA genes and part of a novel protein-coding gene. Quantitative analysis of mRNA expression in blood samples revealed selective overexpression of CNRIP1 and of two lncRNA genes (LOC107985892 and LOC102724389) in all affected members tested, but not in unaffected ones. Qualitative analysis of mRNA expression identified also fusion transcripts involving parts of PPP3R1, CNRIP1 and an intergenic region between PLEK and CNRIP1, in the blood of all carriers of the duplication, but were heterogeneous in nature. By in situ hybridization and immunofluorescence, we showed that Cnrip1, Plek and Ppp3r1 genes are all expressed in the adult mouse cochlea including the spiral ganglion neurons, suggesting changes in expression levels of these genes in the hearing organ could underlie the DFNA58 form of deafness. Our study highlights the value of studying rare genomic events leading to HL, such as copy number variations. Further studies will be required to determine which of these genes, either coding proteins or non-coding RNAs, is or are responsible for DFNA58 HL.


Assuntos
Proteínas Sanguíneas/genética , Calcineurina/genética , Perda Auditiva Neurossensorial/genética , Proteínas de Membrana/genética , Fosfoproteínas/genética , Adolescente , Adulto , Animais , Calcineurina/sangue , Criança , Duplicação Cromossômica/genética , Cromossomos Humanos Par 2/genética , Variações do Número de Cópias de DNA/genética , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica/genética , Predisposição Genética para Doença , Genoma Humano/genética , Perda Auditiva Neurossensorial/sangue , Perda Auditiva Neurossensorial/patologia , Heterozigoto , Humanos , Masculino , Proteínas de Membrana/sangue , Camundongos , Pessoa de Meia-Idade , Neurônios/metabolismo , Neurônios/patologia , Fosfoproteínas/sangue , RNA Mensageiro/sangue , Gânglio Espiral da Cóclea/metabolismo , Gânglio Espiral da Cóclea/patologia , Adulto Jovem
2.
J Biol Chem ; 295(32): 10940-10955, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32532821

RESUMO

Control of gene expression in kinetoplastids such as trypanosomes depends heavily on RNA-binding proteins that influence mRNA decay and translation. We previously showed that the trypanosome protein MKT1 forms a multicomponent protein complex: MKT1 interacts with PBP1, which in turn recruits LSM12 and poly(A)-binding protein. MKT1 is recruited to mRNAs by sequence-specific RNA-binding proteins, resulting in stabilization of the bound mRNA. We here show that PBP1, LSM12, and a 117-residue protein, XAC1 (Tb927.7.2780), are present in complexes that contain either MKT1 or an MKT1-like protein, MKT1L (Tb927.10.1490). All five proteins are present predominantly in the complexes, and we found evidence for a minor subset of complexes containing both MKT1 and MKT1L. XAC1-containing complexes reproducibly contained RNA-binding proteins that were previously found associated with MKT1. Moreover, XAC1- or MKT1-containing complexes specifically recruited one of the two poly(A)-binding proteins, PABP2, and one of the six cap-binding translation initiation complexes, EIF4E6-EIF4G5. Yeast two-hybrid assay results indicated that MKT1 directly interacts with EIF4G5. MKT1-PBP1 complexes can therefore interact with mRNAs via their poly(A) tails and caps, as well as through sequence-specific RNA-binding proteins. Correspondingly, MKT1 is associated with many mRNAs, although not with those encoding ribosomal proteins. Meanwhile, MKT1L resembles MKT1 at the C terminus but additionally features an N-terminal extension with low-complexity regions. Although MKT1L depletion inhibited cell proliferation, we found no evidence that it specifically interacts with RNA-binding proteins or mRNA. We speculate that MKT1L may compete with MKT1 for PBP1 binding and thereby modulate the function of MKT1-containing complexes.


Assuntos
Proteínas de Protozoários/metabolismo , Proteínas de Ligação a RNA/metabolismo , Trypanosoma brucei brucei/metabolismo , Sequência de Aminoácidos , Ligação Proteica , Proteínas de Protozoários/química , Estabilidade de RNA , Proteínas de Ligação a RNA/química , Homologia de Sequência de Aminoácidos , Trypanosoma brucei brucei/fisiologia
3.
Mem Inst Oswaldo Cruz ; 115: e190347, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32428188

RESUMO

BACKGROUND Bacillus Calmette-Guérin (BCG) is considered a promising live bacterial delivery system. However, several proposals for rBCG vaccines have not progressed, mainly due to the limitations of the available expression systems. OBJECTIVES To obtain a set of mycobacterial vectors using a range of promoters with different strengths based on a standard backbone, previously shown to be stable. METHODS Mycobacterial expression vectors based on the pLA71 vector as backbone, were obtained inserting different promoters (PAN, PαAg, PHsp60, PBlaF* and PL5) and the green fluorescence protein (GFP) as reporter gene, to evaluate features such as their relative strengths, and the in vitro (inside macrophages) and in vivo stability. FINDINGS The relative fluorescence observed with the different vectors showed increasing strength of the promoters: PAN was the weakest in both Mycobacterium smegmatis and BCG and PBlaF* was higher than PHsp60 in BCG. The relative fluorescence observed in a macrophage cell line showed that PBlaF* and PHsp60 were comparable. It was not possible to obtain strains transformed with the extrachromosomal expression vector containing the PL5 in either species. MAIN CONCLUSION We have obtained a set of potentially stable mycobacterial vectors with a arrange of expression levels, to be used in the development of rBCG vaccines.


Assuntos
Vacina BCG/imunologia , Escherichia coli/imunologia , Vetores Genéticos/imunologia , Proteínas de Fluorescência Verde/imunologia , Mycobacterium bovis/imunologia , Mycobacterium smegmatis/imunologia , Animais , Escherichia coli/genética , Feminino , Vetores Genéticos/genética , Camundongos , Camundongos Endogâmicos BALB C
4.
RNA Biol ; 15(6): 739-755, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29569995

RESUMO

The Poly-A Binding Protein (PABP) is a conserved eukaryotic polypeptide involved in many aspects of mRNA metabolism. During translation initiation, PABP interacts with the translation initiation complex eIF4F and enhances the translation of polyadenylated mRNAs. Schematically, most PABPs can be divided into an N-terminal RNA-binding region, a non-conserved linker segment and the C-terminal MLLE domain. In pathogenic Leishmania protozoans, three PABP homologues have been identified, with the first one (PABP1) targeted by phosphorylation and shown to co-immunoprecipitate with an eIF4F-like complex (EIF4E4/EIF4G3) implicated in translation initiation. Here, PABP1 phosphorylation was shown to be linked to logarithmic cell growth, reminiscent of EIF4E4 phosphorylation, and coincides with polysomal association. Phosphorylation targets multiple serine-proline (SP) or threonine-proline (TP) residues within the PABP1 linker region. This is an essential protein, but phosphorylation is not needed for its association with polysomes or cell viability. Mutations which do impair PABP1 polysomal association and are required for viability do not prevent phosphorylation, although further mutations lead to a presumed inactive protein largely lacking phosphorylated isoforms. Co-immunoprecipitation experiments were carried out to investigate PABP1 function further, identifying several novel protein partners and the EIF4E4/EIF4G3 complex, but no other eIF4F-like complex or subunit. A novel, direct interaction between PABP1 and EIF4E4 was also investigated and found to be mediated by the PABP1 MLLE binding to PABP Interacting Motifs (PAM2) within the EIF4E4 N-terminus. The results shown here are consistent with phosphorylation of PABP1 being part of a novel pathway controlling its function and possibly translation in Leishmania.


Assuntos
Leishmania infantum/metabolismo , Iniciação Traducional da Cadeia Peptídica/fisiologia , Proteínas de Ligação a Poli(A)/metabolismo , Proteínas de Protozoários/metabolismo , Motivos de Aminoácidos , Leishmania infantum/genética , Fosforilação/fisiologia , Proteínas de Ligação a Poli(A)/genética , Proteínas de Protozoários/genética
5.
RNA Biol ; 12(11): 1209-21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26338184

RESUMO

The eukaryotic initiation factor 4E (eIF4E) recognizes the mRNA cap structure and, together with eIF4G and eIF4A, form the eIF4F complex that regulates translation initiation in eukaryotes. In trypanosomatids, 2 eIF4E homologues (EIF4E3 and EIF4E4) have been shown to be part of eIF4F-like complexes with presumed roles in translation initiation. Both proteins possess unique N-terminal extensions, which can be targeted for phosphorylation. Here, we provide novel insights on the Leishmania infantum EIF4E4 function and regulation. We show that EIF4E4 is constitutively expressed throughout the parasite development but is preferentially phosphorylated in exponentially grown promastigote and amastigote life stages, hence correlating with high levels of translation. Phosphorylation targets multiple serine-proline or threonine-proline residues within the N-terminal extension of EIF4E4 but does not require binding to the EIF4E4's partner, EIF4G3, or to the cap structure. We also report that EIF4E4 interacts with PABP1 through 3 conserved boxes at the EIF4E4 N-terminus and that this interaction is a prerequisite for efficient EIF4E4 phosphorylation. EIF4E4 is essential for Leishmania growth and an EIF4E4 null mutant was only obtained in the presence of an ectopically provided wild type gene. Complementation for the loss of EIF4E4 with several EIF4E4 mutant proteins affecting either phosphorylation or binding to mRNA or to EIF4E4 protein partners revealed that, in contrast to other eukaryotes, only the EIF4E4-PABP1 interaction but neither the binding to EIF4G3 nor phosphorylation is essential for translation. These studies also demonstrated that the lack of both EIF4E4 phosphorylation and EIF4G3 binding leads to a non-functional protein. Altogether, these findings further highlight the unique features of the translation initiation process in trypanosomatid protozoa.


Assuntos
Fator de Iniciação 4E em Eucariotos/metabolismo , Leishmania/genética , Leishmania/metabolismo , Iniciação Traducional da Cadeia Peptídica , Domínios e Motivos de Interação entre Proteínas , Motivos de Aminoácidos , Sequência de Aminoácidos , Sequência Conservada , Fator de Iniciação 4E em Eucariotos/química , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação Eucariótico 4G/metabolismo , Expressão Gênica , Técnicas de Inativação de Genes , Leishmania/crescimento & desenvolvimento , Estágios do Ciclo de Vida , Dados de Sequência Molecular , Fosforilação , Proteínas de Ligação a Poli(A)/química , Proteínas de Ligação a Poli(A)/metabolismo , Ligação Proteica , Alinhamento de Sequência
6.
Biotechnol J ; 19(5): e2400090, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38719592

RESUMO

The production of lentiviral vectors (LVs) pseudotyped with the vesicular stomatitis virus envelope glycoprotein (VSV-G) is limited by the associated cytotoxicity of the envelope and by the production methods used, such as transient transfection of adherent cell lines. In this study, we established stable suspension producer cell lines for scalable and serum-free LV production derived from two stable, inducible packaging cell lines, named GPRG and GPRTG. The established polyclonal producer cell lines produce self-inactivating (SIN) LVs carrying a WAS-T2A-GFP construct at an average infectious titer of up to 4.64 × 107 TU mL-1 in a semi-perfusion process in a shake flask and can be generated in less than two months. The derived monoclonal cell lines are functionally stable in continuous culture and produce an average infectious titer of up to 9.38 × 107 TU mL-1 in a semi-perfusion shake flask process. The producer clones are able to maintain a productivity of >1 × 107 TU mL-1 day-1 for up to 29 consecutive days in a non-optimized 5 L stirred-tank bioreactor perfusion process, representing a major milestone in the field of LV manufacturing. As the producer cell lines are based on an inducible Tet-off expression system, the established process allows LV production in the absence of inducers such as antibiotics. The purified LVs efficiently transduce human CD34+ cells, reducing the LV quantities required for gene and cell therapy applications.


Assuntos
Reatores Biológicos , Vetores Genéticos , Lentivirus , Lentivirus/genética , Humanos , Vetores Genéticos/genética , Meios de Cultura Livres de Soro , Linhagem Celular , Técnicas de Cultura de Células/métodos , Cultura de Vírus/métodos , Células HEK293 , Transfecção/métodos
7.
Saudi Dent J ; 35(3): 263-269, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37091277

RESUMO

Introduction: The consensus among researchers is that early failure of dental implants is due to the lack of primary stability and compressive stress on the peri-implant bone that exceeds the physiological tolerance. Objective: The objective of this work is to propose a new methodology to quantify bone stress during dental implant insertion and to correlate it with primary stability. Materials and Methods: Titanium dental implants with a diameter of 3.75 mm were inserted in a 3.35 mm hole of a synthetic bone of polyurethane (PU) foam with a density of 20 PCF (0.32 g/cm3). During insertion, the insertion torque was measured with a digital torque meter and the bone strain was measured with strain gages located at 2, 4, 6, 8, and 10 mm from the coronal region. Results: The tests showed that the compressive strain is maximum in the third coronal region and decreases in the apical direction. The data also showed that there is a relationship between strain, insertion torque, and the primary stability of dental implants. Conclusion: The stress and strain on the bone progressively decreased from the coronal to the apical third. The maximum compressive stress (0.42 MPa) during insertion of the implant did not exceed bone strength. Insertion of 3.75 mm implants in type D2 bone with a 3.35 mm hole provides adequate primary stability without excessive compression of the bone. Clinical Significance: For the implant-bone combination used in the present study, the compressive stress generated during implant insertion did not exceed the physiological limit of cortical and medullary bone to the point of impairing osseointegration.

8.
Clin J Pain ; 39(7): 334-339, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37083738

RESUMO

OBJECTIVES: Pectoserratus plane block (PSPB) leads to lower postoperative pain intensity. We examined whether PSPB could also reduce the incidence of post-mastectomy pain syndrome (PMPS) in women undergoing breast cancer surgery. METHODS: We performed an extension study of a randomized trial that compared PSPB versus control in women undergoing mastectomy. The primary outcome was any chronic pain at the surgical site or adjacent areas, defined as persistent/recurrent pain lasting ≥3 months. Secondary outcomes included neuropathic pain (score ≥4 in the Douleur Neuropathique 4 questionnaire), use of analgesic/anti-inflammatory drugs, pain intensity through the short-form McGill Pain Questionnaire, and type, frequency, and location of the pain. RESULTS: Of the 60 patients that completed the 24-hour follow-up (short-term trial), 53 (88%) completed the long-term follow-up (27 in the PSPB group and 26 in the placebo group). Six of 27 patients (22%) in the PSPB group and 17 of 26 patients (65%) in the placebo group reported any chronic pain (relative risk [RR], 0.34; 95% confidence interval [95% CI]=0.16-0.73, P =0.005). The risk of neuropathic pain was also lower in the PSPB group than in the placebo group (18.5% vs. 54%, respectively; RR, 0.34; 95% CI=0.14-0.82, P =0.02). There were no differences regarding all other pain-related outcomes considering the patients who developed PMPS. DISCUSSION: The results suggest that, in the long term, PSPB-treated participants were associated with a statistically significantly lower risk of PMPS than those who received standard general anesthesia. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03966326).


Assuntos
Neoplasias da Mama , Dor Crônica , Neuralgia , Humanos , Feminino , Dor Crônica/prevenção & controle , Dor Crônica/complicações , Neoplasias da Mama/cirurgia , Neoplasias da Mama/complicações , Mastectomia/efeitos adversos , Seguimentos , Neuralgia/tratamento farmacológico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Dor Pós-Operatória/complicações
9.
BMJ Open ; 13(4): e067392, 2023 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055197

RESUMO

INTRODUCTION: COVID-19 is an infectious disease that causes severe acute respiratory syndrome. A large variety of exercise capacity tests are used for the evaluation of post-COVID-19 patients, but the psychometric properties of these exercise tests remain undetermined in this population. This study aims to critically appraise, compare and summarise the psychometric properties (validity, reliability and responsiveness) of all physical performance tests that are used to assess exercise capacity in post-COVID-19 patients. METHODS AND ANALYSIS: This systematic review protocol follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols guidelines. We will include studies with hospitalised adult post-COVID-19 patients (aged 18 years or older and with a confirmed diagnosis of COVID-19). The research will cover randomised controlled trials (RCTs), quasi-RCTs and observational studies published in English and performed in the following settings: hospital, rehabilitation centre, outpatient clinic. We will search the following databases with no date restrictions: PubMed/MEDLINE, EMBASE, SciELO, Cochrane Library, CINAHL and Web of Science. Two authors will independently assess the risk of bias (using the Consensus-Based Standards for the Selection of Health Measurement Instruments Risk of bias checklist) and the certainty of evidence (using the Grading of Recommendations, Assessment, Development and Evaluations). According to the results obtained, data will be meta-analysed or reported narratively. ETHICS AND DISSEMINATION: No ethical approval is required for this publication since it will be based on published data. Results of this review will be disseminated via peer-reviewed publications and conference presentations. PROSPERO REGISTRATION NUMBER: CRD42021242334.


Assuntos
COVID-19 , Humanos , Desempenho Físico Funcional , Psicometria , Projetos de Pesquisa , Revisões Sistemáticas como Assunto
10.
Aust Endod J ; 49 Suppl 1: 1-8, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36057963

RESUMO

To evaluate the internal morphology of 100 distal roots of mandibular first molars using micro-CT. Teeth were scanned to characterise: Vertucci type, root length, canal shape, presence and location of accessory canals, and the number of foramina at 4 mm from the apex, presence of root isthmus and the length from the primary canal to the apical foramen. Vertucci type I was found in 57% of cases, followed by V (27%). The most common cross-section 1 mm from the apex was oval (49%) and circular (38%). The average root length was 16.06 mm (16.61-19.02 mm). The mean foramen size was 0.32 and 0.53 mm for the minor and major diameters, respectively. The volume, surface area and SMI were 7.84 mm3 , 68.87 mm2 and 1.52 mm, respectively. Root isthmi were found in 47% of the samples, and the length mean from the primary canal to the apical foramen was 2,03 mm. The internal morphology of the distal roots of mandibular first molars may be complex and shows variations.


Assuntos
Mandíbula , Raiz Dentária , Mandíbula/diagnóstico por imagem , Mandíbula/anatomia & histologia , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/anatomia & histologia , Ápice Dentário/anatomia & histologia , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/anatomia & histologia , Dente Molar/diagnóstico por imagem , Dente Molar/anatomia & histologia , Microtomografia por Raio-X/métodos
11.
PLoS Negl Trop Dis ; 16(10): e0010876, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36288402

RESUMO

BACKGROUND: Spliced leader trans splicing is the addition of a short, capped sequence to the 5' end of mRNAs. It is widespread in eukaryotic evolution, but factors that influence trans splicing acceptor site choice have been little investigated. In Kinetoplastids, all protein-coding mRNAs are 5' trans spliced. A polypyrimidine tract is usually found upstream of the AG splice acceptor, but there is no branch point consensus; moreover, splicing dictates polyadenylation of the preceding mRNA, which is a validated drug target. METHODOLOGY AND PRINCIPAL FINDINGS: We here describe a trans splicing reporter system that can be used for studies and screens concerning the roles of sequences and proteins in processing site choice and efficiency. Splicing was poor with poly(U) tracts less than 9 nt long, and was influenced by an intergenic region secondary structure. A screen for signals resulted in selection of sequences that were on average 45% U and 35% C. Tethering of either the splicing factor SF1, or the cleavage and polyadenylation factor CPSF3 within the intron stimulated processing in the correct positions, while tethering of two possible homologues of Opisthokont PTB inhibited processing. In contrast, tethering of SR-domain proteins RBSR1, RBSR2, or TSR1 or its interaction partner TSR1IP, promoted use of alternative signals upstream of the tethering sites. RBSR1 interacts predominantly with proteins implicated in splicing, whereas the interactome of RBSR2 is more diverse. CONCLUSIONS: Our selectable constructs are suitable for screens of both sequences, and proteins that affect mRNA processing in T. brucei. Our results suggest that the functions of PTB and SR-domain proteins in splice site definition may already have been present in the last eukaryotic common ancestor.


Assuntos
Trypanosoma brucei brucei , Trypanosoma brucei brucei/genética , Trypanosoma brucei brucei/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Splicing de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Íntrons
12.
Genes (Basel) ; 13(12)2022 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-36553541

RESUMO

Hearing loss is the most common sensory deficit, affecting 466 million people worldwide. The vast and diverse genes involved reflect the complexity of auditory physiology, which requires the use of animal models in order to gain a fuller understanding. Among the loci with a yet-to-be validated gene is the DFNA58, in which ~200 Kb genomic duplication, including three protein-coding genes (PLEK, CNRIP1, and PPP3R1's exon1), was found to segregate with autosomal dominant hearing loss. Through whole genome sequencing, the duplication was found to be in tandem and inserted in an intergenic region, without the disruption of the topological domains. Reanalysis of transcriptomes data studies (zebrafish and mouse), and RT-qPCR analysis of adult zebrafish target organs, in order to access their orthologues expression, highlighted promising results with Cnrip1a, corroborated by zebrafish in situ hybridization and immunofluorescence. Mouse data also suggested Cnrip1 as the best candidate for a relevant role in auditory physiology, and its importance in hearing seems to have remained conserved but the cell type exerting its function might have changed, from hair cells to spiral ganglion neurons.


Assuntos
Surdez , Perda Auditiva , Animais , Camundongos , Células Ciliadas Auditivas/metabolismo , Perda Auditiva/metabolismo , Modelos Animais , Peixe-Zebra/genética , Humanos
13.
Rev Gaucha Enferm ; 43: e20210071, 2022.
Artigo em Inglês, Português | MEDLINE | ID: mdl-35613239

RESUMO

OBJECTIVE: To investigate infusion pumps start-up delay according to different brands of infusion pumps, flow rates and intravenous sets priming techniques. METHOD: The experimental study simulated clinical practice under controlled conditions, using a 50 mL syringe with NaCl 0.9% solution, two syringe infusion pumps (A and B), six rates (0.3, 0.5, 1.0, 5, 10 and 20 mL/h), two purging techniques (manually or infusion pump's electronic bolus). Data were analyzed according to mean, standard deviation, Student's t and ANOVA tests (p<0.05). RESULTS: The start-up delay was greater in low rates regardless the priming technique. The electronic bolus increased the infusion pump A accuracy at 0.3mL/h (p=0.010), 0.5 mL/h (p=0.002) and 1.0mL/h (p=0.004). Pump's accuracy in all studied rates and manual IV sets filling was similar. CONCLUSION: In low infusion rates the start-up delay was greater despite the infusion pump brand and electronic bolus improved pumps accuracy.


Assuntos
Bombas de Infusão , Seringas , Humanos
14.
PLoS One ; 17(10): e0275646, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36197937

RESUMO

BACKGROUND: Pulmonary hypertension (PH) is a complex syndrome characterized by increased pulmonary arterial pressure and classified into five groups, according to dyspnea on exertion and systemic muscle dysfunction. These symptoms can be identified using the sit-to-stand test (STS), which indirectly evaluates exercise tolerance and lower limb muscle strength. Previous studies used the STS in PH; however, psychometric properties to understand and validate this test were not described for patients with PH. OBJECTIVE: To evaluate the psychometric properties (validity, reliability, and responsiveness) of different STS protocols in patients with PH. METHODS AND ANALYSES: This is a systematic review protocol that will include studies using STS in patients with PH. Searches will be conducted on PubMed/MEDLINE, EMBASE, SciELO, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science databases following PICOT mnemonic strategy and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P). Rayyan software will be used for study selection. The Risk of bias will be assessed using the Consensus-Based Standards for the Selection of Health Measurement Instruments (COSMIN) tool, while the quality of evidence will be assessed using the modified Grading of Recommendations, Assessment, Development, and Evaluation (GRADE). Two researchers will independently conduct the study, and a third researcher will be consulted in case of disagreement. The psychometric properties will be evaluated according to the COSMIN. This protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO, no. CRD42021244271). CONCLUSION: This systematic review will attempt to identify and show the available evidence on STS for different groups of PH and report validity, reliability, and responsiveness of different protocols.


Assuntos
Hipertensão Pulmonar , Humanos , Hipertensão Pulmonar/diagnóstico , Metanálise como Assunto , Psicometria , Reprodutibilidade dos Testes , Revisões Sistemáticas como Assunto
15.
J Biomed Mater Res A ; 110(4): 812-826, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34783455

RESUMO

Polymethylmethacrylate (PMMA)-based cements are used for bone reparation due to their biocompatibility, suitable mechanical properties, and mouldability. However, these materials suffer from high exothermic polymerization and poor bioactivity, which can cause the formation of fibrous tissue around the implant and aseptic loosening. Herein, we tackled these problems by adding Sr2+ -substituted hydroxyapatite nanoparticles (NPs) and a porogenic compound to the formulations, thus creating a microenvironment suitable for the proliferation of osteoblasts. The NPs resembled the structure of the bone's apatite and enabled the controlled release of Sr2+ . Trends in the X-ray patterns and infrared spectra confirmed that Sr2+ replaced Ca2+ in the whole composition range of the NPs. The inclusion of an effervescent additive reduced the polymerization temperature and lead to the formation of highly porous cement exhibiting mechanical properties comparable to the trabecular bone. The formation of an opened and interconnected matrix allowed osteoblasts to penetrate the cement structure. Most importantly, the gas formation confined the NPs at the surface of the pores, guaranteeing the controlled delivery of Sr2+ within a concentration sufficient to maintain osteoblast viability. Additionally, the cement was able to form apatite when immersed into simulated body fluids, further increasing its bioactivity. Therefore, we offer a formulation of PMMA cement with improved in vitro performance supported by enhanced bioactivity, increased osteoblast viability and deposition of mineralized matrix assigned to the loading with Sr2+ -substituted hydroxyapatite NPs and the creation of an interconnected porous structure. Altogether, our results hold promise for enhanced bone reparation guided by PMMA cements.


Assuntos
Nanopartículas , Polimetil Metacrilato , Apatitas/química , Cimentos Ósseos/química , Cimentos Ósseos/farmacologia , Cálcio , Teste de Materiais , Polimetil Metacrilato/química , Polimetil Metacrilato/farmacologia , Porosidade , Estrôncio/química , Estrôncio/farmacologia
16.
Epigenomics ; 14(14): 851-864, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35818955

RESUMO

Aim: This study investigated the influence of antidepressant drugs on methylation status of KCNE1, KCNH2 and SCN5A promoters and ECG parameters in adult psychiatric patients. Materials & methods: Electrocardiographic evaluation (24 h) and blood samples were obtained from 34 psychiatric patients before and after 30 days of antidepressant therapy. Methylation of promoter CpG sites of KCNE1, KCNH2 and SCN5A was analyzed by pyrosequencing. Results: Three CpG and four CpG sites of KCNE1 and SCN5A, respectively, had increased % methylation after treatment. Principal component analysis showed correlations of the methylation status with electrocardiographic variables, antidepressant doses and patient age. Conclusion: Short-term treatment with antidepressant drugs increase DNA methylation in KCNE1 and SCN5A promoters, which may induce ECG alterations in psychiatric patients.


Assuntos
Antidepressivos , Metilação de DNA , Adulto , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Células Sanguíneas , Ilhas de CpG , Humanos , Canais Iônicos , Regiões Promotoras Genéticas
17.
Elife ; 102021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33783358

RESUMO

Trypanosoma brucei is the causative agent of human sleeping sickness. The parasites' variant surface glycoprotein (VSG) enables them to evade adaptive immunity via antigenic variation. VSG comprises 10% of total cell protein and the high stability of VSG mRNA is essential for trypanosome survival. To determine how VSG mRNA stability is maintained, we used mRNA affinity purification to identify all its associated proteins. CFB2 (cyclin F-box protein 2), an unconventional RNA-binding protein with an F-box domain, was specifically enriched with VSG mRNA. We demonstrate that CFB2 is essential for VSG mRNA stability, describe cis acting elements within the VSG 3'-untranslated region that regulate the interaction, identify trans-acting factors that are present in the VSG messenger ribonucleoprotein particle, and mechanistically explain how CFB2 stabilizes the mRNA of this key pathogenicity factor. Beyond T. brucei, the mRNP purification approach has the potential to supply detailed biological insight into metabolism of relatively abundant mRNAs in any eukaryote.


Assuntos
Proteoma/química , Proteínas de Protozoários/química , Estabilidade de RNA , RNA Mensageiro/química , Trypanosoma brucei brucei/química , Glicoproteínas Variantes de Superfície de Trypanosoma/química
18.
Int J Med Mushrooms ; 23(7): 79-90, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34375520

RESUMO

A wild Amazonian strain of Pleurotus ostreatus (Jacq.: Fr.) P. Kumm. was cultivated using local agroindustrial wastes-açai seeds (AS) and elephant grass straw (EGS)-as substrates and evaluated for its nutritional composition and bioactivities. Basidiomata presented higher contents of protein (27.19%) and dietary fiber (18.57%) when grown on AS, while lipids (2.26%), nonfiber carbohydrates (53.21%), and metabolizable energy (304.02 kcal/100 g) were higher on EGS substrate. Methanolic extracts of P. ostreatus grown on AS also provided a higher phenolic content (31.24 mg gallic acid equivalents/g extract) and greater antioxidant activity, scavenging 82.60% and 91.13% of DPPH· and ABTS·+ radicals, respectively, while chelating ability of Fe2+ was higher on EGS mushroom extracts (74.34%). Hemagglutinating activity of 1,997 HA U/mg protein was observed solely in the aqueous extracts of AS-grown mushrooms. Higher proteolytic activity was observed in aqueous extracts from mushrooms grown on EGS (219.10 U/mg protein), and their saline extract was the sole one with fibrinolytic activity (3.14 mm2). Both substrates and extractions yielded similar activity of protease inhibitors, with higher inhibition of serine than cysteine proteases. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis profiling showed protein bands related to lectins, proteases, fibrinolytic enzymes, and protease inhibitors. Thus, this wild Amazonian strain has great nutritional potential and produces biomolecules that can contribute to important applications in food, health, and industry.


Assuntos
Pleurotus , Animais , Antioxidantes/farmacologia , Alimento Funcional , Humanos , Ostreidae
19.
Polymers (Basel) ; 12(9)2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32961866

RESUMO

This work proposes the use of a dielectric barrier discharge (DBD) reactor operating at atmospheric pressure (AP) using air and sub-atmospheric pressure (SAP) using air or argon to treat polyamide 6.6 (PA6.6) fabrics. Here, plasma dosages corresponding to 37.5 kW·min·m-2 for AP and 7.5 kW·min·m-2 for SAP in air or argon were used. The hydrophilicity aging effect property of untreated and DBD-treated PA6.6 samples was evaluated from the apparent contact angle. The surface changes in physical microstructure were studied by field emission scanning electron microscopy (FE-SEM). To prove the changes in chemical functional groups in the fibers, Fourier transform infrared spectroscopy (FTIR) was used, and the change in surface bonds was evaluated by energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). In addition, the whiteness effect was investigated by the color spectrophotometry (Datacolor) technique. The results showed that the increase in surface roughness by the SAP DBD treatment contributed to a decrease in and maintenance of the hydrophilicity of PA6.6 fabrics for longer. The SAP DBD in air treatment promoted an enhancement of the aging effect with a low plasma dosage (5-fold reduction compared with AP DBD treatment). Finally, the SAP DBD treatment using argon functionalizes the fabric surface more efficiently than DBD treatments in air.

20.
Mar Genomics ; 54: 100789, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32563694

RESUMO

The nutrient and oxygen gradient present in marine sediments promotes high levels of microbial diversity. We applied metagenomics and biogeochemical tools to analyze microbial communities in different sediment depths (0-4 m below sea floor, mbsf) from Guanabara Bay, Brazil, a brackish tropical ecosystem with a history of massive anthropogenic impacts, and a largely unknown sediment microbial diversity. Methanogens (e.g. Methanosarcinales, Methanomicrobiales) were more abundant at 1 mbsf, while sulphate-reducing microbes (Desulfurococcales, Thermoprotales, and Sulfolobales) were more abundant at deeper layers (4 mbsf; corresponding to 3 K Radiocarbon years before present, Holocene Epoch). Taxonomic analyzes and functional gene identification associated with anaerobic methane oxidation (e.g. monomethylamine methyltransferase (mtmB), trimethylamine methyltransferase (mttB) and CO dehydrogenase/acetyl-CoA synthase delta subunit) and sulfate reduction indicated the dominance of Campylobacteria (Sulfurimonas) at deeper sediment layers. Gene sequences related to assimilation of inorganic sulfur increased with depth, while organic sulfur related sequences decrease, accompanying the clear reduction in the concentration of sulfur, organic carbon and chla torwards deeper layers. Analyzes of metagenome assembled genomes also led to the discovery of a novel order within the phylum Acidobacteriota, named Guanabacteria. This novel order had several in silico phenotyping features that differentiate it from closely related phylogenetic neighbors (e.g. Acidobacteria, Aminicenantes, and Thermoanaerobaculum), including several genes (carbon monoxide dehydrogenase, CO dehydrogenase/CO-methylating acetyl-CoA synthase complex subunit beta, heterodisulfide reductase, sulfite exporter TauE/SafE family protein, sulfurtransferase) that relevant for the S and C cycles. Furthermore, the recovered Bathyarchaeota genome SS9 illustrates the methanogenic potential in deeper sediment layer.


Assuntos
Archaea/isolamento & purificação , Bactérias/isolamento & purificação , Baías/microbiologia , Sedimentos Geológicos/microbiologia , Metagenoma , Microbiota , Archaea/classificação , Archaea/genética , Bactérias/classificação , Bactérias/genética , Brasil , Metagenômica , Filogenia
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